Document DMEMM00rGXDK5Nj21YQzjO30n

Organochiorine Pollutants in Peregrines and Merlins Migrating through Wisconsin Robert W. Risebrouch Department of Nutrition*! Science* Institute of Marine Resource* Univerity of Cliforni* Berkeley. C*!ifoml 94720 ' Greoory I. Ei orant Lohorlorv of Omilholoji < ornell Urtivcrsiij, lthc. New York Daniel D. Berger IJ2B N. Jefferon ` Milwaukee, Wisconsin JJ202 , The discovery that the Peregrines (Fatco perefrinus) breeding in the eastern Arctic are laying %thln-shelled eggs and are showing symptoms of _v|[Vproductive failure (Berger et at., this issue) 'j$l$nMfcyrthat this population is beginning to be jpMToy the same extinction process that ils resulted TM the extirpation of breeding Pere grines in many areas of North America and (Hickey,1969; Ratcliffe, 1970). The b of the eastern United States disapefore Ihc nature of the extinction prowas evident, but subsequent research that eggshell thinning had been assowith the population decline (Hickey and >n, 1968). In Great Britain there was piderablc amount of evidence that excesiive mortality of adult birds had been a major e*son for the rapid decline that began around 1955, |^j|feiding with (he introduction of highly oxic Insecticides such as dieldrin into agricul- ural us*(Ratcliffe, 1963; Jefferies and Prestt, 1966). The surviving birds, however, experenced reproductive failures that were characerized by shell thinning, egg breakage, and eatng of the eggs by the adult birds (Ratcliffe, 1.967; Ratcliffe, 1970). Although embryonic mortality may be contributing to the decline in eproductive oapacity of the Ungava Peregrines (Berger**/ at., this issue) the pattern of egg breakage associated with shell thinning now observed in this population appears to be idenical to the symptoms noted previously in south- ern Canada (Hall, this issue), the United States (Hickey and Anderson, 1968) and Great Britain (Ratcliffe, 1970). At the conference convened in Madison, Wisconsin, by J. J. Hickey in 1965 to examine the causes of disappearance of the Peregrine from the eastern United Stales, all conceivable factors were considered in detail. Among these, only environmental pollution was consistent with the pattern of extinction observed in Peregrine populations in both Europe and North America (Hickey, 1969). Since repro ductive failure now appears to threaten the survival of the Arctic populations, it has be come imperative to determine more precisely the particular pollutants responsible. In addition to the evidence relating excessive adult mortality to the use of several of the more toxic of the chlorinated hydrocarbon insecti cides, Ratcliffe (1970) has accumulated a con siderable amount of data relating the shell thinning among British birds of prey to the environmental distribution of organochiorine pollutants, including both insecticides with their derivatives and industrial compounds. The latter consist primarily 6f polychlorinated biphenyls which have become widespread and locally abundant pollutants (Jensen et at., 1969; Kooman et at., 1969; Risebrough et at., 1968). Other pollutants that might be contribu ting to the decline of the North American Peregrines Include mercury and lead. Mercury 247 DSU 029264 STLCOPCB4013226 ........(uni.. i t a. iw i* i <i 248 The Canadian Field-Naturalist Vol. 84 ii Is more widespread in the environment than months old. Seven were bk>psled in 1968 and was previously suspected (Fimreite ei at., this three in 1969. All of the Merlin samples were Issue), waterfowl may accumulate lead from obtained in 1969. Three were adult males, one ingested shotgun pellets (Baglcy and Locke, an adult female, and the remaining three were 1967) and Peregrines preying upon them might immatures of the year. f acquire dangerous concentrations. There is as The biopsy technique has been described yet, how|ve>r, no evidence that links either metal previously (Enderson and Berger, 1968). There at environmental concentrations to the shell have been no indications that this procedure thinning phenomenon. Proof is rapidly accumu harms the birds in any way. Biopsy samples lating, however, that one or more of the chlor have been obtained from Harriers (Circus inated hydrocarbons, particularly the DDT cyancus) that have been observed for many compound DDE, may induce shell thinning months afterwards (Frances Hamcrstrom, per i under both environmental and experimental sonal communication). conditions (Hickey and Anderson, 1968; Porter The adipose tissue biopsy samples were and Wiomeyer, 1969; Heath et at., 1969; frozen, either in acetone-washed glass vials Andersori tt at., 1969). Very small concentra capped with aluminum foil, or in sterile packets tions of |DDE are associated with significant lined internally with aluminum foil which are changes in shell thickness in eggs of the Brown used in medicine for antiseptic gauzes. The Pelican (Pelecanus occidentaUs) (Risebrough, samples were weighed in the laboratory to ob Andersop end Schreiber, unpublished observa tain wet weights and then ground in a Waring tions). Tjhc role of DDE and of other chlorin blcndor with anhydrous sodium sulfate. Lipids ated hydrocarbons found in the environment were obtained by soxhlet extraction for at least such as |dieldrin and the polychlorinated bi six hours with a hot mixture of two parts of phenyls ip producing additional sublethal effects hexane and one part of acetone. The organic that might interfere with reproduction is as yet solvents were removed by evaporation. When unclear. Delayed breeding or abnormalities in small amounts of sodium sulfate were earned behavioup could be associated with the high over into the extract, the lipid was dissolved in rate of steroid degradation caused by the liver petroleum ether and washed with water. enzymes induced by these compounds (Jefferies, The biopsy samples were small. The Pere 1967; Pcakali, 1970). The volume that emerged grine samples averaged 0.49 grams, with a range from thejl965 conference in Madison (Hickey, from 0.0496 to 0.983 gm, and the Merlins 1969) concludes with the statement by Hickey averaged 0.162 gm, with a range from 0.0497 to and Roelje "How much industrial pollutants like 0.5608 gm. Some samples were found to consist the polychlorinated biphenyls have also contri mainly of connective tissue rather than lipid. buted to some of these phenomena promises to The Peregrine samples consisted of an average ! be an absorbing chapter in the research of the of 69% by weight of extractable lipid, with a immediate future" (Hickey and Roelle, 1969). range from 31 % to 91 %. One Merlin sample The present paper reports on the polychlorina consisted of only 5% lipid, the average percent ted biphjjnyts and other chlorinated hydro lipid among the Merlin samples was 35%, and carbons ip fat biopsy samples obtained from ten the highest value was 68%. Peregrines and seven Merlins (Pigeon Hawk, The lipid extracts were dried at 65 for 8-12 Falco cotumbarius) trapped at the Cedar Grove hours, weighed in the beakers, dissolved in Ornithological Station on the western shore of hexane and divided into one or more aliquots. Lake Michigan during the fall migrations of The aliquot analysed for the DDT and PCB 1968 and 1969. compounds was passed through a modified MatcriaJ and Methods Davidow column (Stanley and LeFavoure, 1965). This column, consisting of celite, sul All of the Peregrines were immature birds of furic acid and fuming sulfuric acid, permits the year sod therefore approximately three rapid cleanup with quantitative recov- wmmmm DSW 029265 *8 STLCOPCB4013227 . 84 and were one were ibed here Jure iplea reus tany per- jvere vials kets are The obring pids east s of anic hen Tied d in cra mps ' tins 7 to isist pld. age ha iple ;ent and -12 in OU. CB fied jrt, $ulnlta ov- I ( I t i 1970 Risebrough et. al.: pollutants in Peregrines and Merlins 249 < eric* of the DDT compounds and PCB. of the polychlorinated biphenyls encountered in ! Although not an Important factor for the environmental samples. DDE frequently con j present itudy, it permits much larger amounts stitutes 90% or more of the DDT compounds i of lipid material to be treated at one time than present in wildlife. The electron capture re 1 ' docs the fiorisil method. This procedure, how- sponse of DDE is considerably greater than i ever destroys dicldrln and to determine this that of PCB, and although one of the PCB , compound another method must be employed. compounds emerges at approximately the same Another aliquot of the lipid extract, in hexane, time as DDE, the error introduced in the DDE i was partitioned twice with acetonitrile, the determination is less than experimental error j combined acetonitrile fractions were evaporated even when the total PCB concentration is up to j to dryness, redissolved in petroleum ether, and five time* that of the DDE. Vermeer and Rey I applied to a florisil column. The column was nolds (1970) have commented upon the diffi . rinsed first with 200 ml of petroleum ether and culty in separating the DDT compounds p,p'' 2Q0 ml of 6% ethyl ether in petroleum ether. DDD and p,p'-DDT from PCB. On the DC-200 ! Dieldrin was eluted by passing 200 ml of 15% column, both DDT compounds emerge at | ethyl ether in petroleum ether through the col- approximately the same time as a PCB peak i jrpn. Controls hod indicated that 90% or more (Anderson et al., 1969). On the QF-1 column, j of the dieldrin applied to a florisil column eluted however, there is no interference between p,p'- n this fraction. DDT and any of the polychlorinated biphenyls ; Blank samples consisting of redistilled petro- usually encountered in environmental samples. cum ether analysed through the entire proce- Although many different chlorinated biphenyl i i lure showed no substances that might interfere compounds are released into the environment, with the determination of any of the chlorinated relatively few persist in the higher levels of food hydrocarbons reported here. chains. Moreover, these are found in approxi The extracts were analysed with a Microtek mately the same proportions in environmental ;{as chromatograph equipped with a tritium and samples over wide areas of the world. The it nickcl-63 electron capture detector. Glass chromatograms of the PCB compounds in the i columns were used containing 3% QF-1, or a Peregrines analysed in the present study are j mixture of 3% QF-1 and 10% DC-200, on therefore similar to the chromatograms of Pere , Chromosorb W, 80-100 mesh, acid washed and grine extracts from Mexico, California, and HMDS treated. Amchitka Island (Risebrough, unpublished re Other laboratories (Reynolds, 1969; Armour sults). Moreover, the chromatograms are similar and Burke, 1970) have developed methods for to those obtained from extracts of Brown separating the polychlorinated biphenyls from Pelican eggs from several areas in both North tfOmc or all of the chlorinated hydrocarbons of and South America (Risebrough, unpublished insecticide origin. The polychlorinated biphenyl results). It is frequently possible, therefore, to compounds emerge at different times from the treat the PCB mixture as a single compound gas chromatograph and occasionally a peak may and to obtain accurate relative concentrations coincide or interfere with the peak produced of PCB using any one of the several peaks. The t>y one of the insecticides. We have found it peak emerging at the same time as p,p'-DDD . jK>$sible, however, to quantify PCB, DDE, on the QF-1 column is almost always of the p.p'-DDD, p,p'-DDT, dieldrin and endrin on same height as two of the other peaks. It is the basis of the procedure outlined above, with therefore possible to obtain a crude estimate of out any attempt at separating the PCB. Dieldrin the DDD present without initial separation of )E emerge at exactly the same timb on the PCB. This assumption may be tested and the -200 column, but on the QF-1 column identification of p.p'-DDT and p.p'-DDD con gs no significant interference between and DDE, or between dieldrin and any firmed by saponification (Anderson et al., 1969; Risebrough el a!., 1969). An aliquot of the DSW 029266 STLCOPCB4013228 250 The Canadian Field-Naturalist Vol. 84 extract, in hexane or petroleum ether, is re fluxed in 5j% KOH in ethyl alcohol. The hexane is then sepafated from the alcohol and potassium hydroxide py the addition of water and a sample injected Inp the gas chromatograph. The pro cedure converts both DDT and DDD to their respective [ ethylene derivative^, DDE and DDMU, but leaves the PCB profile of the chromatograms unchanged. Sjnce the profile of the PCB peaks was similar, but not identical to the profile observed in chromatograms of the commercial prepara tion Aroclor 1254, PCB was quantified by comparing the total area of the PCB peaks emerging ajfter DDE with the areas of the same peaks in chromatograms of standard Aroclor 1254. The'ptocedure is therefore arbitrary, but permits Up determination of relative amounts of PCB within the correct order of magnitude of absolute amounts. Moreover, the values ob tained can be readjusted as methodology is jimproved, Results and Discussion Enderson |md Berger (1968) have previously reported op the chlorinated hydrocarbon resi dues found in biopsy fat samples from immature Peregrine* j that were also trapped during fall migration at Cedar Grove, Wisconsin. These samples, analysed by the Wisconsin Alumni Research Foundation in Madison, Wisconsin, contained jan average concentration of 19.4 ppm of DLpE on a lipid basis. DDE concentra tions in the fat of females at the Arctic breeding grounds are much higher, in the order of 300 ppm or hiehcr (Berger et at., this issue). The ten Peregrine samples analysed in the present sturdy contained 17.9 12.3 ppm DDE, 0.23 0.34 ppm p,p'-DDD, 0.71 0.68 ppm p,p'-DDT,ll8.8 12.5 ppm total DDT (DDE -f p,p'-DD;D + p,p'-DDT), and 52,2 32.3 ppm PCB. $even samples were analysed for dieldrin, Which averaged 0.4Q 0.64 ppm. All residues are expressed on an extractable lipid basis, wkh the 95% confidence limits of the standai^ error of the mean. The values for p.p'-DDD and p.p'-DDT are lower than those previously reported by WARF, Inc., presum ably a result of interference by PCB in the earlier determinations (Anderson el at., 1969). The dieldrin values are equivalent to those previously reported and there is no significant difference in the DDE concentrations. On a lipid basis, the average values reported by WARF, Inc. were 19.3 ppm DDE, 0.8 ppm DDD, 1.2 ppm p,p'-DDT and 0.3 ppm dieldrin (Enderson and Berger, 1968). First year immature Peregrines migrating from the Arctic have therefore low residues of DDE. Unfortunately little is known about the relationships among dietary levels of DDE and PCB, equilibrium concentrations of these com pounds in various tissues, and the limes required to achieve an equilibrium concentration. The low concentrations found in these Peregrines presumably reflect therefore both the age of the birds, which possibly has not permitted them to accumulate the high concentrations found in adults, and lower levels of contamination found in some of the prey species. An understanding of the pharmacodynamics of DDE and PCB in birds is one of the conspicuous deficiencies in our knowledge in the field of pollution ecology. Within several ecosystems so far studied, the concentrations of DDE in birds tends to parallel the concentrations of PCB. The ratio may be approximately one to one, as in San Francisco Bay (Risebrough et at., 1968). DDE is several times more abundant than PCB in several Pacific marine ecosystems (Risebrough et at., 1968), but in Florida, PCB is approximately three times as abundant as DDE in the Brown Pelicans (Risebrough, Grcss, Anderson and Schreiber, unpublished manuscript). The cor relation coefficient between the DDE and PCB concentrations is frequently highly significant. These observations have suggested that the ratios observed reflect the local fallout pattern of the DDT and PCB compounds, and that the DDE and PCB show similar patterns of accu mulation, concentration and excretion in the birds and possibly other members of the ecosys tem. Among the 10 Peregrine samples analysed, PCB was more abundant than DDE by ap proximately three time*. The correlation co- i ! i i t i J * i t i i ii t m DSW 029267 I I STLCOPCB4013229 ? 84 < the *69). hose leant lipid \RF. . 1.2 ;r*on ating c of t the and comulred The rincs .(the m to id in ound tding )B in es in logy. I, the rallcl iy be CiSCO vetal veral t al., lately rown and corPCB icant. i the ittem it the accuv the osys- yaed, / ap i co- 1970 . Risebrouoh et. al.: Pollutants in Peregrines and Merlins 251 efficient it 0.8897, which ii significant at the shell thinning associated with egg breakage, 0.001 level. Although it is not known from disappearance of the eggs, and eating of the ! which area of the Arctic these birds have come, eggs by the adult birds (RatclifTe, 1970). In the i the results suggest that over a considerable area Ungava population of Peregrines in the eastern 1 of the tundra ecosystems occupied by the Perc- Arctic, shell thinning and egg breakage are now i giines, this ratio reflects the local fallout pattern contributing to reproductive failures (Berger et of DDE and PCB, al., this issue). The evidence available to date ! The four adult Merlins averaged 302 ppm suggests, however, that PCB is not a cause of DDE (139-704) in the lipid fraction. This value the shell thinning observed in many populations I may be compared with an average concentra- of birds. No correlation between thinning and | tion of 392 ppm in the lipid of 9 breeding PCB was found in the eggs of the White Pelican I Peregrines from the Mackenzie River region (Pelecanus erythrorhynchos) (Anderson et al., j (Endcrson and Berger, 1968), 725 ppm }n >969) or in eggs of the Great Blue Heron ' . the fat of four adult Peregrines from Alaska (Ardea herodias) (Vermeer and Reynolds, ! (Cade et a!., 1968) and 334 ppm in the lipid of >970). An analysis of approximately 200 eggs I 9 adult Peregrines from Ungava (Berger et al., f >he Brown Pelican from both eastern and t this issue). Merlins therefore may possess al- western North America has shown that DDE i most the same level of contamination as the rather than PCB is associated with the shell , , Peregrines and might therefore be expected to thinning (Risebrough, Gress, Anderson and ' show symptoms of shell thinning. The concen- Schreiber, unpublished ms.) Whenever corre- [rations of total DDT in the adult Merlins >ations between PCB and shell thinning have ! averaged 314 ppm. 96% of the DDT residua been observed, as in Double-Crested Cormor- | in these Merlins therefore consisted of DDE. "ts (Phalacrocorax auritus), PCB is also cor- | The PCB concentrations averaged 196 ppm related with DDE (Anderson et al., 1969). (44-467). The samples were not analysed for Peakall (1970) has reported that p,p'-DDT dieldrin. delays egg laying in the Ringdove (Streptopelia In the three immatures, DDE averaged 49.3 rlsoria) and that the delay is associated with ppm (10.8, 18.6 and 119.3), total DDT aver- *w concentrations of atradiol in the blood j aged 50.3 ppm, and PCB averaged 28.6 ppm early in the breeding cycle. Peakall had earlier (5.7,29.0and 51.2). With the exception of one reported (in Risebrough et al., 1968) that immature Merlin that contained 18.6 ppm DDE technical DDT, p,p'-DDE, and PCB induce the and 51.2 ppm PCB, a ratio similar to that found synthesis of liver enzymes that degrade estradiol, in the Peregrina, all other Merlins contained an<> PCB >* a more potent enzyme inducer more DDE than PCB. With the one immature than DDE. Delayed breeding may therefore ! excepted, PCB was significantly correlated with he one of the environmental effects of PCB, an i DDE (r = 0.9820, p less than 0.001, four effect that could be critical to Arctic-brecding j degrees of freedom). Most of the Merlins, birds which must complete their reproductive therefore, appear to be coming from a region of cycle within a restricted period of time, the boreal forest where the pollutant fallout A recent investigation in Japan of the pattern is different from that in the tundra "Yusho" or Rice Oil Disease has traced the ecosystem occupied by the Peregrine. cause to rice oil contaminated by chlorinated When PCB was found to be present in Perc- biphenyls (Katsuki, 1969). Both the contamin- jrines, occasionally in high concentrations, it ated rice oil and the Japanese commercial PCB teamed likely that these pollutants were con- produce symptoms when fed to chicks similar tributing to the reproductive failures associated to those observed in the "chick edema" syn- with population decline (Risebrough el of., drome (Goto et al., 1969). This disease of - 1968). The dominant symptom of reproductive chicks was first observed in the United State* failures of the Peregrina in Britain has been in 1957, and among the symptoms were accu- !\ i i DSW 029268 mm STLCOPCB4013230 252 The Canadian Field-Naturalist Vol. 84 niulatlon of fluid in the pericardial sac and in ihc abdominal cavity, subcutaneous edema, and liver and kidney damage (Verrett, 1970). Chlorinated dibenzo-p-dioxins have been shown to be ope of the groups of chlorinated synthetic compounds that produce this disease (Higgin botham ex. at., 1968). These compounds have also bcjtn shown to be present in the herbicide 2,4,5-T and induce both mortality and embry onic deformities in chicks at very low concen trations (Verrcit, 1970). A similar group of compounds, the chlorinated dibenzofurans, are almost las toxic (Schulz, 1970). These resemble the chlorinated biphenyls in structure and might be derived from them. Whether they are now present^ in the environment and pose a threat to wildlife promises to be Man absorbing chapter in the research of the immediate future" (Hickc^ Bnd Roelle, 1969). Acknowledgements The research was supported by the National Science'Foundation grants GB 6362 and GB 11649.' Literature Cited Anderson, D. W,, Hkkey, I. J,, Rbebrotigh, It W,, Huftfck D. F,, and Chrlrten.es>, R. E- 1969. Sig nificance of chlorinated hydrocarbon residue* to breeding pelican* and cormorant*. Canadian FieldNalurjaligt 83(2): 91-112 Armour. 1. A. and Burke, I. A. 1970. Method for teparating polychlorinated biphenyl* from DDT and ils analpg*. Journal of Ibe Association of Official Analytical Ch*n>i*ts JJ: 761-768. Bagky, |G. E. and Locke, L. N. 1967, The occur rence of kad in tissue* of wild birds. Bulktin of Environmental Contamination and Toxicology 2: 297-305. Berger, D. D-, Anderao.1, D. W, Wearer, I. D* Risebeougk, R. W, and Reynolds, L. 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Marked DDE impairment of Mallard reproduction in controlled studies Nature 224: 47-48. Hickey, J. J-, editor. 1969. Peregrine Falcon Population*: Their Biology and Dectine. Univeriity . of Wiicomln Press, Madison. 596 pp. Hkkey, J. I. and Andersow, D. W. 1968. Chlorin ated hydrocarbon* and eggshell change* in raptorial and fish-eating birds. Science 162: 271-273. Hkkey, J. I. and Roelk, J. E. 1969. Conference summary and conclusion*, In Peregrine Falcon Population*: Their Biology and Decline, J. J. Hkkey, ed. University of Wisconsin Prei*, Madison, pp. JJ3-J67. Higginbotham, G. R-, Hwang, A-, Fires!owe, D-, Ver rsft, J., Res*, J-, and Campbell, A. D. 1968. Chemical and toxicological evaluation* of isolated and lynthetk chloro derivative* of dibenzo-p-dioxin. Nature 220: 702-703. Jefferies, D. J. 1967. The delay in ovulation pro duced by p.p'-DDT and it* possible ignificance in the field. Ibis 109: 266-272. ' Jefferies, D. I. and Prertt, I. 1966. Post-mortem* of Peregrine* and Lanner* with particular reference to organochlorine residue*. British Bird* 59: 49-64. Jensen, S_, Jobnek, A. G, Oksoft, M, and Otlerllnd, G. 1969. DDT and K"B in marine animal* from Swedish water*. Nature 224: 247-250. Katvukt, 8. 1969. Reports of the Study for "Yutho" (Chlorobiphenyl* Poisoning). Fukuoka Acta Medica 60: 407. Kotman, J. H., Ten Notvtr d Brauw, M. Cm and De Vo#, R.' H. 1969. Chlorinated biphenyl* in fish, mussel* and birds from the River Rhine and the Netherlands Coastal Area. Nature 221: !I26- 1128. . Peakali, D. B. 1970. p.p'-DDT: Effect on calcium metabolism and concentration of estradiol in the blood. Science 168: 592-594. Porter, R, D. and Wiemtyer. S. N. 1969. Dieldrin and DDT: Effects on Sparrow Hawk eggshells and reproduction, Scknce 165: 199-200. RnicHffr, D. A. 1963. The status of the Peregrine In Great Britain. Bird Study 10: 56-90. Raeclifft, D. A, 1967. Decrease in eggshell weight in certain birds of prey. Nature 215: 208-210. RatcUffc, D. A. 1970. Changes attributable to pesti cides in egg breakage frequency and eggshell thick ness in some British* bird*. Journal of Applied Ecology 7: 67-115. t. DSW 029269 I I I J I I 1 t II II | ) I I t ! l I STLCOPCB4013231 I >1. 84 caused n Japvfodica i; The Press. aturtl- 1969. ludion Falcon vtrsity . hlortnptorial erence Falcon J. J. id iton. 1968. .dated Jioxin. n pro rice in ems of nee to 49-64. tfUnd, i from 'usho" ledka. and lyls in ie and 1126- alcium in the icWrin lit and egrine weight 0. i petithici.pplied i ; ; j I i , i j 1 ; I , j | j i , I ( 1 I I t i i i 1970 Rjscbrouom et. al.: Pollutant^ in Peregrines and Merlins 253 Reynold*, L. M. 1969. Polychlorobiphenyls (PCBT) and their Interference with pesticide residue analysis. Journal o( Environment*!' Contamination and Toxicology. 4: 128-14). Rlarbrough, R. WM Rtkhe, P,, Peakal!, D. 1H Herman, 8. C., and Kkven, M. N. 1968. Polychlorinated biphenyls in the global ecosystem. Nature 220; 1098 1102. RJwbcossfh, R. W,, Reich*, P,, and Okott, H. 8. 1969. Current Progress in the determination of the polychlorinated biphenyls, Bulletin of Environ mental Contamination and Toxicology. 4; 192-201. Schulz, K. H. 1970. Clinical picture and etiology of chloracne. Reprinted In: Effect* of 2.4.J.-T on Man and the Environment Hearinft before the Subcommittee on Energy, Natural Resource*, and the Environment of the Corotpltte* on Commerce, United Statet Senate. Serial 91-60. U.S. Govern ment Printing Office, Washington, D.C. Stanley, R, L, and LeFavovre, H. T. I96J. Rapid digestion and clean-up of animal tissues for pestkide residue analysis. Journal of the Association of Offi cial Analytical Chemists. 48; 666-667. Varmetr, 1C and Reynold*, L. M. 1970. Organochlorine reilduet in arjuatk birds in the Canadian Prairie Provinces Canadian Field-Naturalitt $4; 117-1)0. Vemtt, J. 1970. Statement before the Subcom mittee on Energy, Natural Resource*, and the Environment. In; Effects of 2,4^-T oa Man and the Environment. Serial 91-60. U.S. Government Print ing OflVoe, Washington, D.C. Received October, 1970 Accepted October, 1970 DSW Q2927Q STLCOPCB4013232